WPC wall siding Poplar fiber, HDPE Looks like nature wood Lifetime: 20 years ISO, SGS, CE About WPC: WPC (wood plastic composite) ... wood fiber) 10% chemical additives (Anti-UV agent, Anti-oxidation agent, stabilizers, colorants, anti-fungus agent, coupling agent, reinforcing agent ... like nature wood.3. Waterproofing, fireproofing, Mildew-resistant, anti-UV.4. Less cracking, less warping.5. No need ...